Protocol Field in IPv4

Duration: 2 min

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Module outline

  1. HPSC Interview Preparation: Interview Preparation
  2. Python Language: Introduction to Python, Tokens, Variables, Data Types, I/O, Operators & Expressions, Control Flow & Looping, Collections & Strings, Functions & Modules, File Handling & Data Analysis, DSA using Python
  3. Data Structure & Algorithms: Introduction to DS, Array, Stack, Queue, Linked List, Tree, Graphs, Hashing, Algorithm Analysis, Sorting Algorithms, Minimum Spanning Trees, Time Complexity Analysis, Graph Theory, Shortest Path Algos
  4. Computer Networks: Introduction to CN, Data Communication, DLL: Access Control, DLL: Flow Control, Data Link Layer - Ethernet, Net Layer: IPv4 & Proto, Net Layer: IP Addressing, Transport Layer Services, TL: Congestion & UDP, Application Layer, Hardware basics, Network Security
  5. Computer System & Organisation: Basics of COA, Cache Memory Organization, Input Output Organisation, Pipelining, Instr Formats & Modes, Control Unit Design, Programming the Basic Computer
  6. Database Management System: Basics of DBMS, ER Diagram, Relational Model & Functional Dependencies, Keys & Integrity Constraints, Normalization (1NF - BCNF), Decomposition Properties & 4NF, SQL, File Organization & Indexing, Transaction Management, Concurrency Control
  7. Operating Systems: Introduction to OS, Process Management, CPU Scheduling, Process Synchronization, Deadlock, Threads & Process Creation, Memory Management, Virtual Memory, Disc Scheduling
  8. Digital Logic & Circuits: Digital Systems & Boolean Basics, Logic Gates & Hardware, Boolean Expression, Boolean Minimization, Combinational Circuit, Sequential Circuits, Number System, Number Representation
  9. Theory Of Computation: Introduction to TOC, Deterministic FA (DFA), Non-Deterministic FA, Regular Expressions, Grammar, Regular Language Properties, Pushdown Automata & CFG, Turing Machines, Moore & Mealy Machines
  10. Compiler Design: Intro to Compilers, Lexical Analysis, Grammar & CFG, Syntax Analysis: Top-Down, Syntax Analysis: Bottom-Up, Semantic Analysis & SDT, Intermediate Code Gen, Code Optimization, Run Time Environment
  11. Software Engineering: Fundamentals of Software Engineering, Software Requirements and Quality Assurance, Software Design, Estimation and Metrics, Software Testing, Software Maintenance and Configuration Management, Data Warehousing & Mining
  12. Introduction to Emerging Trends: Emerging Tech Trends
  13. Digital Society & Cyber Law: Society, Law & Ethics
  14. HPSC PGT Previous Year Paper:
  15. HPSC Assistant Professor Previous Year Paper:
  16. Live Sessions: HPSC Live Sessions, EMRS TGT/PGT Live Class
  17. Full Mock Test:
  18. HPSC PGT - MOCK Test Series:
AI summary & chapters

AI Summary

An AI-generated summary of this video lecture.

This short lecture segment explains the Protocol field in an IPv4 header. The instructor highlights that this 8-bit field identifies which transport-layer or network-layer protocol the payload should be delivered to upon arrival at the destination. A layered diagram shows TCP and UDP under Transport, while ICMP, IGMP, and OSPF appear under Network, all feeding into a Payload block inside a Datagram. A table titled “Some protocol values” lists ICMP 01, IGMP 02, TCP 06, UDP 17, and OSPF 89. A hand-drawn box labeled “H” and “P L” is added beside the header to illustrate the header-payload relationship, with an arrow from the Protocol field pointing toward it. The on-screen text notes that in TCP/IP, the data section of a packet, called the payload, carries the whole packet from another protocol.

Chapters

  1. 0:00 – 2:00 00:00-02:00

    The instructor introduces the Protocol field in an IPv4 header, pointing to it in a header diagram and explaining that this 8-bit field identifies the protocol to which the payload should be delivered at the destination. A hand-drawn box labeled “H” and “P L” is added to the right of the header, with an arrow from the Protocol field pointing toward it. A layered diagram shows Transport protocols TCP and UDP, and Network protocols ICMP, IGMP, and OSPF, all dotted-arrowing into a teal Payload block inside a Datagram. A table titled “Some protocol values” lists ICMP 01, IGMP 02, TCP 06, UDP 17, and OSPF 89. On-screen text states: “In TCP/IP, the data section of a packet, called the payload, carries the whole packet from another protocol.”

  2. 2:00 – 2:22 02:00-02:22

    The slide remains focused on the IPv4 header table with the Protocol field (8 bits) highlighted by a double-headed arrow, alongside fields like Time-to-live and Header checksum. The hand-drawn “H”/“P L” box and the layered Transport/Network diagram persist, reinforcing that the Protocol value determines whether the payload is handed to TCP, UDP, ICMP, IGMP, or OSPF. The protocol-values table (ICMP 01, IGMP 02, TCP 06, UDP 17, OSPF 89) stays visible as the instructor gestures toward the diagram, concluding the explanation of how the field maps payload delivery to specific protocols.

The core teaching point is that the IPv4 Protocol field (8 bits) acts as a selector for the next-layer protocol responsible for processing the payload. The instructor uses three complementary visual aids: (1) a header diagram with the field highlighted, (2) a layered network diagram separating Transport (TCP/UDP) from Network (ICMP/IGMP/OSPF) protocols converging on a Payload block, and (3) a numeric table assigning protocol numbers. The hand-drawn H/P L annotation bridges the abstract header field to the concrete packet structure, showing that the header governs how the payload is interpreted. For exam revision, students should memorize the common protocol numbers (ICMP 01, IGMP 02, TCP 06, UDP 17, OSPF 89) and understand that the field’s value is consulted at the destination to demultiplex the payload to the correct protocol handler.

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